I hope it is OK to ask this Q on this forum...not quite sure of the rules..But here goes...I'm going to climb aconcagua in Fe09 and need to get the best deal from detroit to mendoza...BA and 20hr bus or Santiago...Airfares are a littel cheaper to BA and if I do Santiago, I will have to pay 130USD in reciprocity fee...so what do I do? If anyone has researched this...let my know. thanks and pardon the forum breach if it apply's

You can fly into Mendoza directly on LAN (you'll stop in Santiago, but won't clear customs or pay the reciprocity fee since you're in transit). Try Orbitz or American's website. It's a little more expensive than flying into EZE, but that's partially offset by the cost of the bus from the airport/downtown/Mendoza. Personally, I've done it both ways and would much rather have the two extra nights out in Mendoza. Good luck.

You might try flying Southwest from Detroit to LAX for about $250 and then get a flight from LAX to Mendoza on LAN. Try the LAN website and Priceline, expedia, etc... I got my tickets from LAX to MDZ for about $1,100 with taxes and fees etc... Depending on your dates it also looks like flights with AA and LAN are comparable in price if you book directly out of Detroit via one of the online discount sites like priceline, etc...

If you opt for (1) just make sure you have several hours between your Southwest arrival and your LAN departure so that you can pick up your luggage and re-check-in to the international flight.

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Another thing to try is checking LAN at various times of day (AM, PM, Graveyard) every day for a couple of weeks straight. I saw fluctuations of over $400 round trip but no apparent pattern. I gambled when they hit like $1200 on LAN, checked Priceline immediately, and got them for about $525 each way + fees.